Under the Lone Moon
by WilliamSurehoof
Summary: Out of touch and unprepared, Luna finds herself alone. Celestia is in grave danger, unable to be woken by any remedy or spell, and a faceless evil threatens Canterlot. With her subjects doubting her and the kingdom in turmoil Luna intends to make her sister proud, keep an unstable Equestria from falling apart, and bring justice to whatever dared to try and take her sister from her.


Tia would likely be very cross with her.

Well, perhaps only a tad bit cross, now that the moon princess had gotten over her initial shock of having dropped the tiny ceramic cup. A once gleaming and beautiful piece of fine china, inlaid with flakes of diamond, had met a brutal end against the worn marble of Luna's balcony, dissolving into a hundred tiny pieces where it had struck and scattered, the dark contents spilled in a wide spray from the spot.

"You know, dear sister," Celestia would be likely to start off, "the mayor of Las Pegas would be most unhappy to see his gift being treated so mercilessly."

"Oh, hush," muttered the princess to herself, in no mood for the silly mock scolding her diurnal sister was so fond of giving, even if it was just imaginary scolding. To be honest, she was rather upset about the loss of the cup as well, if only because its contents were now splashed across the cold stone.

The cup had been one of a dozen, given to Princess Celestia as a gift during the time that Luna had been...away. As Tia explained it, the mayor of Las Pegas had gotten the idea that he could woo a princess with expensive gifts, but these cups had lain just as forgotten as the others until Luna had started to try to find uses for them.

The cup was expensive, but unmissed. Much worse was the loss of a particularly good brew of mint tea.

"Horsefeathers," the normally regally-composed princess muttered, though not without a tinge of guilt at her language over something so small. The etiquette of old was deeply ingrained in her, and though she had picked up on some modernizations, the tendency for modern ponies to curse was something Luna had conflicting thoughts on. It was so... undignified... but she couldn't help muttering choice foul words to herself as she learned them. Her favorite was 'horsefeathers'.

Perhaps she enjoyed the chance to finally be relatively uncouth without anyone caring.

The moon princess turned her attention to what had caused her to drop the cup in the first place: a twinge of startlement at nothing in particular that she could tell. Was she being jumpy? Perhaps she was… it'd been a busy night and, though exhausted, Luna was still somewhat jittery. At any moment she expected to have to set out again and see to the protection of her little ponies. But no… she'd done enough tonight. In a short while her sister would be raising the sun, and then the nightly troubles would become her older sibling's daily headache.

At least for the next twelve hours, mused Luna. She'd asked her sister to go through the trouble of setting the moon as well, as a favor so that she could finally relax, and she had a feeling that Celestia would make sure to extract some form of payment from her at some point. Knowing her prankster of a sibling, that likely meant she'd leave some form of task left undone for tomorrow night, _just for Luna_.

The Moon Princess quietly sighed, casting her eyes from side to side to survey the damage, and decided that it wouldn't be all that difficult to clean up herself. Before her...absence...she wouldn't have hesitated to call somepony to clean the shattered remains in her stead. Now, given the somewhat more 'leveled' social standing of ponies, it seemed it would be irresponsible for her to not take up the task herself.

Luna called on her magic, and pale blue light radiated from her horn. Encircling the pieces of broken china in her magic, she started to pull them into one place, resolving to use a spell to repair the cup if she didn't miss any pieces in pulling it all toget-

A sharp, sudden, and _immense_ pain lanced from the tip of her horn all the way down, and Luna gave a startled gasp as though she'd been physically struck. It certainly felt like she had been. Her magic flickered and went out like a doused candle, and the alicorn recoiled backwards almost expecting something more to happen… but there was nothing more, save for a dull headache from the sensation.

Luna felt like something had touched her; the sensation was as though something had grabbed onto her horn and firmly _yanked_. The same sort of sensation as before, in fact, which had caused her to drop the cup in the first place. Was there something wrong with the cup? Was there something wrong with _her_?

Where her sister was unused to being under threat, the Moon Princess found such was a routine part of her duties in the night; she was suddenly awake and afire, preparing herself for what she felt might be inevitable attack. Surely, this must be the case. Night was not yet over, after all, and until the sun rose again there would be ..._tasks_ to face.

A minute of silence passed, broken only by the distant sound of a chirping insect far below her balcony. Nothing came, nothing went, save for the dull ache in Luna's horn.

Was she under attack? Had some nightmare followed her? Surely whatever it had been would have shown itself by now; it was exceptionally rare but sometimes things would, more or less, 'follow her home'. Surely this must be the case?

What else could it be?

Still, only silence. The Moon Princess strained her senses, hoping for something to be revealed, and offer answer to the startlement just a moment ago, but yet still nothing happened.

At long last, she released a slow breath she hadn't realized she was holding. Perhaps she wasn't under threat at all.

Luna tensed as she heard a resounding clatter and bang, from behind her. Through the door to her balcony, her bedchamber, and the foyer, she could see all the way to the heavy door of her chambers, which had just been thrown roughly and unceremoniously open.

A white-coated unicorn, clad in heavy golden plate, stood panting in the open doorway for a moment, looking around in desperation; a member of the Dayguard division of the Royal Guard, those that normally watched over Celestia and the castle during the daylight hours. "Princess Luna!" the stallion managed to get out.

Behind him shortly followed one of Luna's own, a pale grey unicorn stallion who wore no helm, only his cuirass that bore the blue circle of the Nightguard. He had likely been preparing to change posts, as evidenced by the disarray of his kit. "What are you _doing_?!" the Corporal hissed, clearly not happy at all. "You can't barge in on Her Majes-"

"Princess Luna!" called out the Dayguard again, reaching up and throwing his own helm to bang and clatter on the floor so he could better see without the metal getting in the way. He didn't seem inclined to care about Luna's doorpony whatsoever. Luna didn't recognize him; she only knew the faces and names of perhaps a few of Celestia's guards, and since her return she had little time to learn more than a dozen of the names of her own, a group that had been neglected and reduced to near extinction in her absence. Normally the details of such things was left to Celestia, or Prince Shining Armor.

The Moon Princess was in no mood to worry about the intrusion; something was amiss. Amiss of the most horrible sort.

"**Guard! Speak!"** Luna called out to get his attention, forgetting herself in her rush to find out what had happened; her sister's watchers were unused to the thunder of an alicorn's voice when raised, as unlike Luna their charge had long since ceased raising hers. The call made the guard gasp and turn to face through the open doorways, out to her balcony, and for a moment he struggled to find his voice.

"Y-your majesty! It's Princess Celestia!"

_Tia. Oh no, Tia, _Luna felt a sudden sensation of dropping in the pit of her stomach. The merest inkling that something had happened to her sister was… just…

"Please! Princess Luna!" entreated the Royal Guard stallion again.

Behind him, the formerly angry doorguard was turning about, talking to some other out of view. "Get reinforcements, now!"

"Who?" said a strained voice.

"_Everypony! Every last one!_"

Luna didn't waste time with asking for further explanation; she would find out herself. She, for a moment, was about to reach out to her magic and call upon it to bring herself to her sister with a teleportation spell… but stopped just short. _No. Something isn't right. There is no coincidence here._

She would forgo magic, until she knew what had happened. She turned to her balcony again, shuffling her wings open and flaring them wide. There was simply no time, in her mind, to waste in getting airborne. She threw herself, wings wide, from the balcony, catching the air beneath her in the fall and starting to power upwards.

_Tia is at her own chambers, almost certainly. That, or the courtyard, _Luna reasoned. _We'll discover which in short order._

It didn't take long to find that the former was the case; the courtyard was empty. The princess angled her wings and turned about sharply, working to gain altitude in the cool air; Celestia's chambers were relatively near to her own, though slightly higher up and facing towards the east where Luna's faced towards the west.

When the Moon Princess alighted on her sister's balcony, she was met by no less than ten members of the golden-clad Royal Guard. They were startled at her sudden appearance, and two even seemed about to draw their weapons. Some already had even before her arrival; they were panicked. Why?

The dropping sensation in Luna's stomach returned. Soon, it felt as though her stomach had dropped entirely from out of her body, and the ground felt soon to follow.

Celestia was behind the guards, who parted at Luna's approach, flat on her side against the white stone of the balcony. Her mane, normally gleaming as though aglow itself, was dark and motionless around her where she had fallen, and she looked to be entirely limp. Her eyes were closed.

"P-Princess Luna!" stuttered one of Celestia's guards. "We don't know what happened, there was this big flash of light, and she just-"

"Your Majesty!" interrupted a black-clad member of the Nightguard, charging into the room adjoining the balcony. "Are we calling 'To Arms'? Are we-"

"The Sun Princess is-" broke in the Dayguard that had been previously speaking.

"**Be silent!**" The thunder of Luna's voice cut the imminent bickering suddenly short, and the Dayguard around Luna recoiled at the sound.

Luna ignored them for the time being, and found herself, almost without knowing how, kneeling next to her sister. There was no sign of blood. No sign of struggle. No sign that anything had happened. Was she sick? Was she injured?

Without thinking, Luna pressed her cheek and ear to the chest of her older sister; she was warm, even hot to the touch, as she always was… and she was breathing. But it was shallow, labored, and irregular.

"...big sister?" Luna muttered. She hoped that her sister would wake. She hoped that her sister was somehow, impossibly, unfathomably asleep and would wake to her voice. "...Tia, please…?"

There was no hint of response from the prone form of the Sun Princess. She was alive, but certainly not asleep.

"Y-your majesty…?" said one of the nearby Dayguard; he seemed to be hoping for good news, if unlikely. "What should we do?"

What should she do? Luna could barely think of an answer to the question. She didn't know. Celestia was always the one who knew, and she was the one who needed help. But protocol dictated that she be the one to make decisions in such a case.

What would Celestia have done?

"Guard, fetch…" she paused. Who? "...fetch the castle apothecary."

"W-which one, your highness?"

They had more than one? "Horsefeathers… all of them. And we will move Princess Celestia from the balcony, we need to have her in a safer location."

"Princess Luna, your highness!" called another guard, this one being one of Luna's. "Are we… are we under attack?"

"We… I'm not sure," Luna trailed off. Were they? They could be? "We… _I_ intend to find out. Assume we are, and bring the castle to arms until we know more. I don't want my sister without at least ten ponies watching her at all times." This last she directed at the golden-clad guard near her. She scoured the Dayguards' shoulderplates, searching for rank insignias; not a single one of these were over the rank of Corporal. "Where is the Dayguard Commander? He should be summoned immediately!"

"Your highness, he's off duty. I think h-he's asleep in-"

"**As is his charge, isn't she?!**" interrupted Luna, standing and suddenly angry. The guards, even her own, recoiled as she towered over them, and those that were at the door and about to enter to join the growing platoon of onlooking soldiers seemed about to turn and go elsewhere at the bellow. "And so long as Princess Celestia sleeps, he should not! We will have him here at once!"

It seemed, suddenly, as though Luna felt sure of herself. She'd felt awkward and helpless but a moment ago, but called to action she felt perhaps some of her old self return, a touch of strength from a time when she had been less humble. She would see to her sister's protection; Celestia would trust her to do that, and more.

"Nightguard, who here is of highest rank?"

"Ma'am, I am!" called a stallion that was entering the bedchamber adjacent to the balcony. He shoved his way forwards through the growing crowd of guards, grumbling. "Who woke up the whole damn garrison?! Clear this bucking room, this isn't a circus!" Soon he stood in front of Luna, saluting with a hoof; she recognized him, both his leathery wings and rank insignia. This was one of the very few of Luna's guard that was a natural-born batpony. "Sergeant Shale, reporting as ordered, Highness!"

"Sergeant, find the Nightguard Commander and appraise him of the following:" Appraise him of what, exactly? Luna still wasn't sure. "...until further notice, Canterlot Castle is on the defensive, and we are to assume we are threatened. The Dayguard will see that Princess Celestia is taken to the…" What was that room? "...apologies, the chamber built after the changeling attack."

"Siege vault, yes ma'am!" At least Shale seemed to know exactly what Luna meant. Celestia would be, perhaps, more safe there; that was the entire purpose of the room, after all. "Ma'am, what is the threat? I-if you don't mind me being so bold as to ask, your highness!"

Luna offered the best answer she could: "... we will know in due time, once my sister is safe. Tell the Commander he should have a message delivered by magic to Prince Shining Armor in the Crystal Empire immediately; we need him here." Though the Nightguard and significantly-larger Dayguard each had division commanders, Shining Armor remained the head of both… though his position ruling the Crystal Empire alongside young Mi Amore Cadenza left him almost entirely absent in the past year, if not longer.

Princess Luna broke away from the Sergeant and turned back to her sister, returning to the stone floor next to her. There was still no sign of movement, but the shallow breathing continued. Something was gravely wrong, Luna could feel it from every extremity into the very core of her heart; something was _so very wrong_ that it _hurt_.

Behind her, Shale was already moving into action. "Corporal, you're in charge of this room until I get back, see that Her Highness is guarded!"

"Y-yes, Sergeant!" said the Corporal, the still helmless guard that had earlier been posted near Luna's chambers.

"And get this _bucking room cleared!_"

_It's still night,_ Luna suddenly realized. Her eyes reluctantly left her sister to look upwards. Above, the sky was still black and dotted in familiar stars, and the glow of dawn hadn't even begun. Celestia hadn't yet raised the sun. The moon, however, was already lowered from the sky, leaving it darker than she was ever used to seeing it.

The night was not yet over. And so long as it was night, the Moon Princess still had tasks to face.

She didn't know if she alone could face them.


End file.
